Twenty-three-times Cup winners Athletic Bilbao were dumped out in sensational circumstances by tiny island side SD Formentera, who sneaked a 1-0 win at San Mames with a header by Alvaro Muniz deep in stoppage-time to reach the last 16 for the first time with a 2-1 aggregate victory.
A hat-trick from Giovani dos Santos helped Barcelona to a 5-3 victory away to relegated Real Murcia.
Real Madrid stayed on course to retain the Spanish title after they recovered from a first-half sending-off to clinch a 1-0 win over relegation-threatened Real Murcia at the Bernabeu on Sunday. With six matches left to play, Real lead the table on 69 points, nine ahead of Barcelona, who were held 2-2 at Recreativo Huelva on Saturday.
Samuel Eto'o scored two late goals for Barcelona in a 4-0 romp at home to promoted Real Murcia in the Primera Liga on Saturday.
Leaders Real Madrid were held to a 1-1 draw away to promoted Real Murcia in the Primera Liga on Saturday, allowing arch-rivals Barcelona to close to within two points in the standings.
Chelsea will pay 30 million euros ($33.54 million) for the player, three of which will be based on performance, the Spanish champions said on their website.